David Lawrence Sackett is widely regarded as “the father of evidence based medicine,” which is arguably the most important movement in medicine in the past 25 years. But he is perhaps most appreciated by doctors for repeating his residency in medicine some 20 years after first training because, although a professor in the medical school, he “wasn’t a good enough doctor.” This was an act of great courage and shows how Sackett, although at one time a professor in Oxford, had no pomposity whatsoever. Of Oxford he said, “They have 20 ways of saying ‘interesting,’ all of them negative.”

David Lawrence Sackett is widely regarded as “the father of evidence based medicine,” which is arguably the most important movement in medicine in the past 25 years. But he is perhaps most appreciated by doctors for repeating his residency in medicine some 20 years after first training because, although a professor in the medical school, he “wasn’t a good enough doctor.” This was an act of great courage and shows how Sackett, although at one time a professor in Oxford, had no pomposity whatsoever. Of Oxford he said, “They have 20 ways of saying ‘interesting,’ all of them negative.”

The third son of a bibliophile mother and artist-designer father, Sackett grew up in a suburb of Chicago. He remembered his large Victorian house as filled with love, neighbourhood kids, border collies, bagpipe and classical music, and books for every age and interest. He lived in such houses all his life and was always a voracious reader.

After completing his medical training at the University of Illinois, Sackett was in 1962 drafted into the US Public Health Service as a result of the Cuban missile crisis. In Buffalo, New York, he met epidemiologists, was diverted from his career in bench science, and became interested in how the methods of epidemiology could be applied to his “first love,” clinical medicine. He called this combination “clinical epidemiology,” a term that had been used in the 1930s, only then it aimed to pull physicians away from individual patients while Sackett wanted them to go in the opposite direction. In 1963 he read a paper by Alvan Feinstein, a clinician and researcher at Yale, on boolean algebra and clinical taxonomy and wrote him a “fan letter.” Feinstein then became a mentor for Sackett.

Another mentor for Sackett was Walter Holland, professor of clinical epidemiology at St Thomas’s Hospital Medical School in London. The legend is that when appointed in the early ’60s Holland wanted his department to be called a department of social medicine but was told that if he did he would never get a visa to the US. So he proposed the name epidemiology but was then told that his staff would then be paid preclinical (smaller) salaries, so he opted for the term clinical epidemiology. Sacket did a sabbatical with Holland later in his career, but in 1966 it was Holland who suggested Sackett to John Evans, who was starting a new medical school at McMaster University in Hamilton, Canada.

After getting a letter from Evans “out of the blue” Sackett went to visit him, but, he didn’t want to leave the US, was 32 years old, and had, he told me in an interview, “never done anything.” Evans contacted him because he wanted “a different kind of medical school” and wasn’t taken with the traditional public health people in Canada. Sackett didn’t want the job and so could be very frank. Evans asked him about what sort of department of social medicine and community medicine they should have in the new school, and Sackett answered “none.” His point was that all clinicians should be concerned about these issues. In fact Evans had already reached the same conclusion.

Evans’s next question was what sort of course should there be to teach medical students epidemiology and statistics. Again Sackett answered “none,” arguing that these disciplines needed to be taught within the clinical disciplines. “Otherwise it would be just as awful as everywhere else. The students would hate the faculty. The faculty would hate the students. And it would be a shambles.” Again it’s what Evans wanted to hear: there weren’t going to be any courses in anything, students would learn from the problems of patients. This concept of medical education had come from William Spaulding, a Toronto physician and psychiatrist who had thought deeply about medical education and was another of Sackett’s mentors.

As Sackett put it, Evans mistook “a novice for a sage” and asked him to come back for a second interview. Eventually Sackett was appointed and started in 1967, with the first students arriving in 1969. “I was scared,” Sackett said, “I was a kid, I’d never really had a research grant, my previous publications were on basic science, so who would want to come and work with me or give me money for research?” Yet he was ambitious. He recognised that being scared was not compatible with being a new chair in a new medical school. He needed to be “incurably optimistic, convinced that everything was going to be great, incredibly positive, and get his kicks out of the successes of others.” So Sackett displayed those characteristics and attracted outstanding staff and lots of money. The author Kurt Vonnegut, a hero of Sackett’s, says you become what you pretend to be, so be careful what you pretend.

Much later, when researching a history of McMaster, Sackett found a report on his department by an external reviewer from many years previously that described him as “having an air of grandiosity.” Evans had circled the word and written in the margin, “Thank God, otherwise he never would have had the guts to try.”

After some years of the McMaster programme Sackett and his colleagues decided that they wanted to share what they were doing and wrote a series of articles on what they called “critical appraisal” (the phrase “critical thinking” was dropped because basic scientists objected to the implication that they weren’t thinking critically). The articles appeared in the Canadian Medical Association Journal in 1981, and at that time, while on sabbatical in Dublin, Sacket began to write Clinical Epidemiology: a Basic Science for Clinical Medicine, which started in 1985 as a book about critical appraisal and, with research methods added in the third edition, evolved into the “the bible of evidence based medicine.”

Sackett, together with Drummond Rennie, deputy editor of JAMA, and others published Users’ Guides to the Medical Literature, some 40 or so articles in JAMA that were collected together. Then came The Rational Clinical Examination, which aimed “to make a science out of taking a history and doing an examination,” enterprises fundamental to medicine that had not been scientifically studied.

Evidence based medicine, said Sackett, goes beyond critical appraisal because it combines research evidence with clinical skills and patients’ values and preferences. You have to be able to make the diagnosis and then discuss options with patients. Sackett used the example of non-valvular atrial fibrillation, where the patient has a small risk of a stroke. Should the patient take warfarin and so risk a bleed? Most patients see a stroke as about four times worse than a bleed. You combine that with number needed to treat and number needed to harm and conclude that you are about 11 times more likely to help rather than harm a patient by treating him or her with warfarin.

In 1994 Sackett arrived in Oxford, where he became a clinician at the John Radcliffe Hospital as well as director of the Centre for Evidence-Based Medicine. He was interested in spreading evidence based medicine not just to Oxford but to the rest of the UK, Europe, and beyond. He visited most of the district general hospitals in the UK and many in Europe, and he would begin his visit by doing a “post-take ward round” with young doctors, showing evidence based medicine in action. In 1998 he made 100 visits. The young doctors realised that they could challenge their seniors in a way that wasn’t possible with expert or authority based medicine. It was liberating and democratising.

Paul Glasziou, a general practitioner and professor of evidence based medicine at Bond University in Australia, 25 years later still remembers vividly a ward round with Sackett: a student used a decision aid to calculate the chances that a patient had anaemia and the clinicians consulted a systematic review on the value of treating the patient with ferritin. It was completely different from the traditional ward rounds he’d experienced.

Evidence based medicine took off like wildfire, Sackett believed, for two main reasons: it was supported by senior clinicians who were secure in their practice and happy to be challenged, and it empowered young doctors—and subsequently nurses and other clinicians. Sackett thought that spreading evidence based medicine from Oxford would be a 10 year programme, but the spread was so fast that after four years he realised he wasn’t needed any more.

Evidence based medicine did, however, produce a backlash, particularly, said Sackett, “among middle level guys who were used to making pronouncements.” A Lancet editorial in 1995—entitled “Evidence placed medicine, in its place”—was offensive to Sackett, who had been involved in the civil rights movement, because it evoked the familiar American phrase “black guys are OK, in their place.” Sackett was very hurt by this editorial, which felt like “a supreme put down by the British establishment.” One response was an editorial in The BMJ by Sackett and others, entitled “Evidence based medicine: what it is and what it isn’t.” That editorial, said Sackett, “turned the whole thing around.” It carefully refuted all the complaints made against evidence based medicine: it wasn’t old hat, impossible to practice, cookbook medicine, the creature of managers and purchasers, or concerned only with randomised trials.

Subseqently Sackett became founding coeditor of the journal Evidence Based Medicine and the first chair of the Cochrane Collaboration, a body that perhaps more than any other has been responsible for spreading evidence based medicine across the globe.

Sackett was well known for arguing that after 10 years of being an expert you should stop—because your views are given too much weight and get in the way of new thinking. He was an expert on compliance, but in 1980 stopped all his work on compliance, and in 1999 he gave his last lecture on evidence based medicine, in Krakow, Poland.

His work done at Oxford completed, Sackett retired from clinical practice in 1999 and began what he described as his eighth career, by returning to Canada and setting up the Trout Research and Education Centre, where he read, researched, wrote, and taught about randomised clinical trials. Altogether he published 12 books, chapters for about 60 others, and about 300 papers in medical and scientific journals. One of his most popular pieces was a three part essay on the importance of saying “No.”

A big, warm, and emotional man Sackett lived his final years with his wife, Barbara, in a wooden cabin beside a lake that was frozen for much of the year. Sackett always described himself as a man of the north. They had many family and friends to stay and would invite them all to canoe on the lake.

Asked by students and colleagues for the reasons for his success, Sackett included among several reasons: “An insuppressible capacity for finding and injecting fun into everything I did (sometimes to the distress of others).” He also included “The enduring, loving support, encouragement, and understanding of Barbara and our four sons.”

He leaves Barbara; four sons; and grandchildren.

Notes

Cite this as:BMJ 2015;350:h2639

Footnotes

Professor of clinical epidemiology, McMaster University, Hamilton, Ontario, 1967 to 1994; physician, John Radcliffe Hospital, Oxford; and director, Centre for Evidence-Based Medicine 1994-99 (b 1934; q University of Illinois 1960; Officer of the Order of Canada 2001); died from cholangiocarcinoma on 13 May 2015.